We sometimes have volunteers that pop up here and there in our Wildscape. I often like to let them "go" until I can figure out whether they're desirable or not. In other words, are they native? Well, this plant appeared this past spring. I figured out what it wasn't–a ragweed. But what? One expert I often query was perplexed. So last week I asked @sambiology on iNaturalist. Bingo! He nailed our plant! This is a paper mulberry (Broussonetia papyrifera), which is native to Japan and Taiwan. Here in the States, this plant is considered to be invasive.
So the mystery is solved. Now an executive must be staged.